Depends what is used as a "loophole". Take away the ability for people to be paid in dividends which can effectively reduce your tax from 50% down to 37 ish and you will all but kill off expansion in small busineses as the owners of these use money from the business to top their earnings back up. However when you are talking about a corporate entity that is clearly taking millions from UK residents for goods, and then shipping that money out of the country by using some offshore licensing rubbish, then thats a different matter.
Definitely a balancing act and like a lot of things i.e. NHS, Royalty etc etc that are essy to criticise but very hard to sort out.